India To Build World's Largest Solar Plant 253
ananyo writes "India has pledged to build the world's most powerful solar plant. With a nominal capacity of 4,000 megawatts, comparable to that of four full-size nuclear reactors, the 'ultra mega' project will be more than ten times larger than any other solar project built so far, and it will spread over 77 square kilometres of land — greater than the island of Manhattan. Six state-owned companies have formed a joint venture to execute the project, which they say can be completed in seven years at a projected cost of US$4.4 billion. The proposed location is near Sambhar Salt Lake in the northern state of Rajasthan."
Epic-scale photovoltaic (Score:5, Interesting)
According to TFA, this will be a huge photovoltaic plant. But as I understand it, solar thermal is more efficient, and for a large centralized project like that, I would have expected solar thermal.
http://en.wikipedia.org/wiki/S... [wikipedia.org]
Does anyone know why they are going photovoltaic for this project?
Photovoltaic certainly does have some pluses: it's simple, no moving parts. But for a project of this capacity I should think they would go for the most efficient solution.
Plus a thermal solution with molton salt [wikipedia.org] would provide a nontrivial amount of storage, for power after dark.
So, what am I missing? Does India have lots of factories making photovoltaic cells or something?
Re:Epic-scale photovoltaic (Score:5, Interesting)
So, what am I missing? Does India have lots of factories making photovoltaic cells or something?
Why not Solar Thermal? As I understand it...
1. Lack of local companies that make solar thermal equipment (aka CSP or concentrated solar power).
2. Lack of experience with large deployment unlike PV like 50:1 in MW to date (no experience means no reference projects to predict ROI for contracting companies or investment banks)
3. Lack of water resources for cooling (most simple solar thermal needs reliable-access to cooling water to avoid equipment malfunction).
Of course India could deploy a minimal water solar thermal solution (e.g., air cooled or maybe Heller towers), but they have even less experience with that and most government funded programs require a minimum make-local percentage.
Re:Epic-scale photovoltaic (Score:4, Interesting)
It's cheaper.
There is a glut of photovoltaics on the world market ever since the european countries cut the subsidies. Most notably Spain and, more recently, Germany. Which is responsible for the sudden drop in prices. It is not better technology, despite what the propaganda claims (otherwise solar power companies wouldn't go bankrupt all over Germany).
And yes, solar thermal is more useful on paper. Unfortunately it takes up just as much space as PV and needs lots of water for it cooling towers. However, solar thermal depends on very stable weather patterns. It cannot tolerate cloudy days very well - so you'd best build it in a desert, where cooling water is kind of rare as you can imagine. You'd need 24 million cubic meters of cooling water per year for an equal sized solar-thermal power plant.
What would be needed for PV to work is storage. Hydrogen/methane seems to be the only plausible/scalable solution so far. Unfortunately, even with the best technology we have on the planet, you'll need at least 3kWh electricty to get 1kWh of electricity back out of storage. Thus the average power of the power plant will drop from 800MW down to about 500MW, assuming that at least some part of the power will be used directly. (The amount of storage that is necessary depends on a lot of factors, mostly what power is available from other sources and how variable the weather patterns and seasons are. So 500MW is just a ballpark figure.)
Re:I love numbers but.... (Score:4, Interesting)
India already has nuclear weapons, as do Pakistan, so I'm not sure what nuclear proliferation you're talking about.
For most of December, the central European wholesale price of electricity was negative. Yes, that means people paid other people to take their electricity away. This was a direct result of reliance on wind power. This is _not_ a good thing.
The total construction and decommission costs of wind farms and the problems associated with them have not been realised yet. They may well be lower, but until we actually start taking them down and getting rid of the tonnes of concrete and other infrastructure for each turbine, we don't really know.